Amy, my name is Clare and I'm 35 years old. But obviously I was also 17 before.
Lets change the mindset here. You speak of guys using you. Ahem, but, lets think about that. You're using guys to feel better about yourself, right?
Soooo, with this new consiousness, lets presume that you wait a few weeks, and you build up potentials (guys that you think are worth being with).
Dressing slutty is a state of mind too. Unless you have huge boobs that hang out your top, you're pretty safe. Think classy, and you walk classy, walk classy and you talk classy. Doesn't matter if your boots touch your knees and your skirt touches your bum.
And don't listen to those other b*^ches who care to judge, with a little self-control on your behalf, they'll be so left in the dust
I'm not sure if my experiences resonate with your own, but for what its worth;
I was a really shy girl up until about the age of 15. I found that in some ways I was quite different personlity-wise from many of my more "popular" female peers and it made me feel like a bit of an outsider. Basically I hung out with the "fringe" groups. When the hormones started kicking in and I started developing into a young woman, I found that I attracted a fair bit of attention from the guys. It was flattering and I played to that quite a bit.
I finally started to have something in common with the "popular" girls - boys. And I moved into a different social circle. I think that its possible that I attributed my social status to guys, and that I went out of my way to attract them. I dressed rather provocatively, and I must say that I did sleep with more boys than the average girl.
I think for me, the big change came when I had the opportunity to make friends from outside of my school. The whole social hierarchy thing of my school started losing its importance, and I found that I wasn't nearly so worried about who showed me attention there or not. I started meeting other new friends, through my new friends, and guys too. This enabled me to better choose who I wanted to give extra attention to. And my self-esteem grew steadily as a result.
As I say, your situation might be quite different to mine, and I'm not even sure if you're in school or college or neither. But if you are, perhaps taking up an activity that will move your social focus away from where it is now might be the key to liberating yourself from a "self-destructive" cycle.